Health care providers look for three characteristic features of polycystic ovary syndrome (PCOS): absence of ovulation, high levels of androgens, and cysts on the ovaries. Having one or more of these features could lead to a diagnosis of PCOS. If your medical history suggests that you might have PCOS, your health care provider will rule out other conditions that may cause similar symptoms.
Some of these conditions include:
- Excess hormone production by the adrenal glands, called adrenal hyperplasia (pronounced uh-DREEN-l hahy-per-PLEY-zhuh)
- Problems with the function of the thyroid gland
- Excess production of the hormone prolactin by the pituitary gland, called hyperprolactinemia (pronounced hi-per-pro-lak-tuh-NEE-mee-uh).
- Take a full family history. Your health care provider will ask you about your menstrual cycle and any history of infertility. He or she also will ask you whether you have a mother or sister with PCOS or with symptoms like yours, as PCOS tends to run in families.
- Conduct a complete physical exam. Your health care provider will do a physical exam and look for extra hair growth, acne, and other signs of high levels of the hormone androgen. He or she also will take your blood pressure, measure your waist, and calculate your body mass index, a measure of your body fat based on your height and weight.
- Take blood samples. Your health care provider will check the levels of androgens, cholesterol, and sugar in your blood.
- Do a pelvic exam or ultrasound to check your ovaries. During the pelvic exam, your health care provider will insert two fingers into your vagina and press on your belly to feel for cysts on your ovaries. To help see cysts in your ovaries, he or she might recommend an ultrasound, a test that uses sound waves to take a picture of your pelvic area. Your health care provider also will check how thick the lining of your uterus is; if your periods are irregular, the lining of your uterus could be thicker than normal.
Because there is currently no universal definition of PCOS, different expert groups use different criteria to diagnose the condition. However, all the groups look for the following three features:3
- Menstrual irregularities, such as light periods or skipped periods, that result from long-term absence of ovulation (the process that releases a mature egg from the ovary)
- High levels of androgens that do not result from other causes or conditions, or signs of high androgens, such as excess body or facial hair
- Multiple cysts of a specific size on one or both of the ovaries as detected by ultrasound
Your health care provider will use one of three different methods to diagnose PCOS. One method requires only features 1 and 2 above for a PCOS diagnosis; another requires any two of the three features above for a PCOS diagnosis; and the last one requires feature 1, plus one other feature listed above for a PCOS diagnosis.